Plastering machine



March 26, 1935. J, A. BLANKEN 1,995,414

PLASTERING MACHINE Filed Aug. 12, 1933 2 Sheets-Sheet 1 ATTORNEY March26, 1935. J. A. BLANKEN PLASTERING MACHINE Filed Ailg. 12, 1933 I I INNTOR XIKEYQ oaw v ATTORNEY 2 Sheets-Sheet 2 Patented Mar. 26, 1935mseeiase maxim i Abpiicatibh-Augdstl-Z} 1933; Serial Na 6845791 Myinvention relates to'a ln'acliine' fdf dliv ering plaste'r fro'rnasupfaly tankjeither'dire'ctls f or'it'o' a wall which is beingplastered, or'tcapositien con venient" for the plasterer to apply the"plaster w; 5 the walls. I'haveshow'n-the invention embodied in orapplied to a'portabl'e truck which"pe'riiiits the machine to be wheeledfrom onfe 'loatiori' to another and it is' preferably' of slicli'w'idth'as'to" permit it to'be'passed through doorways, sotl'ia't 10* it maybe-move'd about a building'to beiii con- .venient location to theparticular "room or' wall which is to be plastered;

It is desirable in machines of this"type','-t'o feed the plast'erregularly as desired; an'dat'th'e re:

quired speed; to properly' supply thew'orknianwith enough plaster tobe'a'pp'lid tdthewallat whatever speedhe may operate; an'dthe presentma: chine is designed to accomplish this.

In'machines for feedingplaster-there "has be'en difliculty infeeding-theplaster as r'equ'ired avoiding compacting'or plugging'oii-the plaster in--v the {machine and the various" pipes* and hfOSe'jthrough-which it passes';and the present machine meets-theserequirements successfully.- c c To a great extent the methodof'propellirigithe plaster through the machineand the hose has -a" greatdeal to do with the successful propulsion-of the-plaster; If-certaindevicesyareused'iofipro; pellingthe plaster-, they will causemoreor-1ess-* so separation -of *the- -1iquid and solid content of; the

material andcausethe-latter to plug up the hose as-well--as-parts oi themaehine.-, v It'is an objectofp-thepresent inyention-tofirstreceive-"the plaster-{rem a-supply tankyhopper;orother containerintothe;s hell-of a 'pump; and to force-the plaster from this pump casing orshell, bymeans of apiston,--into-a-;1 ece iyer chamber tank; which'hasapprox-1111ately the :same capacity as;the pump; -sj -i lia a r ac strken i e umpw 40 this chamber is filled with a charge of-plastei 1 iv nacam er I i 9 2, r -c P? diihil the charge is beingpumped therein, aiterwhich it is closed. A valve between the pumpand theireceiiliii'cHainBefi's' thii closed'ito prevent the "re;

other ipoin't and "may" be d a lanning-ails;

tioiiof the pu'm'p 7 Figure 6 is" asimilar Vie the time the and Figure'7 is 'a-sect 7--7of Figure'fi."

showizigithe puiiip ational"view"-takeri onthe line the" truck is shownas provided'with castefs df rollers 2 which permit it to' 'b'e'wheelefalong a?" floor to place'it'ir'i "a convehieiitpositiontb'befiear the work:- On-tliis truck there issi'ipported a?- framework3fo1mir'ig an elevated suir'sp'o'rt for vari 40" ous parts of themachine: "'O'n tl'f uppefi awce the machine there is 'a-"tank -,0r;container? f6? holdinga' s'upply'" o"fplaster" or similar materialwhichis to bedistributed'bythe'machinegand ndesired the material; includingtheiiqui'd'orvskltef 4 and the plaster and' other" ingredients? may -e-i7 mixed orstirred this container 'so that the mixaiing'ope'rationrwillitakeplaceatithe-niachinef I 6 whichdrivesan"='endless belt": meme newer 6* piston is making its upwardstroke? engages also around the pulley wheel 8 which is fixed to a shaft9 and is mounted cross wise of the machine in suitable bearings 10.

and drives the worm gear 18 and through this the shaft 19 which runslongitudinally of the machine is driven at a much lower speed than .15

the speed of the motor. On this shaft 19 to the right in Figures 1, 3and 4, there. is fixed a sprocket wheel 20 which drives the endlesschain 21 and this chain in turn drives the sprocket wheel 22 which isfixed to the shaft 23. The latter extends into the tank 4 and issupplied with the usualpropeller device (not-shownl-for mixing thematerial contained within the feeding tank. Even though the material maybe mixed at somelocation other than the machine, it is desirable toagitate the material within the tank in order to prevent separation ofthe moisture arid solid] content beforethe material is deliv-..

ered from the machine.

At the left-Figure 1 and Figure- 3 I have shown an ordinary compressor24 which is driven from asecond pulley-25 onthe shaft of the motor,

, by means; ofan endlc ss belt'26 travelling over this pulley and alsotravelling over a pulley 2'7 on theshaft of the compressor. 1 have notshown the interior constructionof the compressor becausethe ordinarystock compressor may -be used for this purpose. 7 The air compressed inthe compressor is delivered by means of a; pipe; 28 to a pressure tank29 in which the. compressed air is stored under pressure until fed tothe receiving chamber, to be hereinafter de scribed.

I have found that in the operation of a machine of this type it isdesirable to maintain the air in the compression tank 29 at about thirtyor thirty-five pounds; that if the pressure ex-' ceeds; this to a greatextent, ;the'machine;will

not operate as satisfactorily and there .is a tendencyof the liquid andsolid contents to be separated. V c I At the front end of the machine Ihave shown mounted on theframework 30 a vertical or upstanding post 31at about the middle of the machine. This post ,or standard forms asupport for variousmovable'parts as will bexdescribed. I

have shown mounted on a stud shaft32. at the upper endof the standard, alever having one arm 3,3,extendin'g to the left in Figure 2, and-to thefree end .of-lwhich is pivotally, connected a pistonv rod 34the lowerend of which piston is connected. with the piston of a pump.

The other arm 35 of this leverhas pivotally connected with it a link 36and the. other end of thislink isjpivotallyconnected with a cam disc 37which ismounted on the shaft. The cam disc 37. is revolved :in the.direction. indicated by the arrow inFigure 2 because it is fixed to oneend of the longitudinal shaft 19 which has previously beendescribed-andwhich: isdriven from the motor;;by the belts andpulleys above described.

The revolving motion of the cam disc 3'7 causes this discto act as acrank and to operate the link 36 ;'f or the purposeof rocking :the lever33, 35 thus movingthe pump pistonup and down. i

. Attheleftin Figure 2 andin Figures 5 to 7 On this same shaft.

purpose of opening the-valve. V

54 of this lever is connected by a wire or rod 55' with one. arm 56-of abell ,crank which is pivoted I'have shown a simple form of pump casing38 consisting of a cylinder which at the bottom end has connectedthereto a pipe or hose 39 through which the material is discharged bythe action of the pump.

There is arranged to move vertically up and down in this pump casing apiston 40 which is shown as in the form of a circular disc of slightlysmaller diameter than the bore of the casing 38. This piston ispivotally connected as shown at 41 by a hinge pin which is pivotallymounted upon a plate 42 extending vertically and connected as by rivets.with the lower portion of the piston rod 34 which is the piston rodconnected with the rocking lever described above.

Around the hinge pin 41 there is coiled the spring 43 one end of whichengages the under side of the piston 40 for the purpose of applyingslight'upward pressure to the latter in order to move it against thestop member 44 which is formed by bending the end of the piston rod, as

shown in Figure 6. a In this position the piston lies at right angles tothe axis of the pump casing and is in position to force the materialfrom the pump casing on-the downward stroke of the piston rod. Thepiston may be swung downwardly in opposition to the light spring 43 asshown in Figure 6 while the piston rod is moving upwardly, in order toallowthe piston to be moved 7 above thematerial in the pump casing.

VThere isa chuteor hopper 45 which is connected with one end of thesupply tank 4 and into which the material from the tank feeds bygravity. The'lower and smaller end of this chute engagesthe upper end ofthe pump casing, as

shown in Figures 5 and6, so that the material is fed "down through thischute into the pump casing. r

At the right in Figure 2 I have shown a hollow I body 46 which forms areceiving chamber to receive the material which .is delivered by .thepump, in which the "material is momentarily stored until 'it is drivenout bythe compressed air. This member is simply a hollow cylinder, and.between the lower end thereof and the lower end of thepump casingthereis aipipe 39 for thereto. At the upper endof the receiving chamber 46there is anothervalve 49 which is also adapted to be operated by a leverarm 50 The purpose of this valve is to permit the discharge of air fromthe charging chamber while the 7 material is being forced therein by thepump in order that the'charging chamber may be filled with the material.This valve simply permits the discharge of air from the charging chamberinto the open air.

There is a pipe or hose 51, one end of which is connected with thepressure tank 29 and it ex tends forwardly and is connected to the upperend of the charging chamber 46, preferably just below the valve 49. Inthis pipeor hose there.

is a valve 52 for controlling thesupply of comhas a vertically, moving;spindle 53 and this is operated by means of the lever 54 which ispivotedto a portion of the valve casing and it has one pressed air tothe charging chamber. This valve arm 55 adapted to press on'the spindlefor the 7 The other arm cam disc the lever arm 60 is'first swungupward-- ly and then moved downwardly following the roller or pin 62part of the way.

The lower end of'thelever arm 60 is pivotally connected witha link 63and the other end of this link is pivotally. connected with the leverarmwhich operates thevalve 49. There is another link 64 having'one endconnected pivotally with the same pin which unites the link 63 andthe-lever arm 50. Theother end of this 1 link 64 is pivotally connectedwith a pin on the end of the valve 47.

lever arm 48) operates the 'The lower end-of; the charging chamber 46isprovided with anozzle 65 and to this is connected" one end'ofa flexiblehose fifi-which' is adapted to convey the material to the point ofapplication. The other end of this hose may simply discharge thematerial into a receptacle where the plasterer is working, but'preferably'there -is-a-fan shaped spout '67 connected with the endof-the hose, to

discharge the material through afltaentral'fslot or aperture inthetrowel"-68.; The qrneinber '67 is shown provided with handles 69 bywhich the operator may manipulate the trowel .in applying the plaster toa wall or'ceiling; I do not claim in the present case any patentablefeatures in the trowel or nozzle.

Operation I Assuming the machine is in operation, that is,

the motor 5 is driving the various parts of the machine, the followingoperations will take place; that is to say, the compressor 24is'continually driven through the pulley 25, the-belt 26, and the pulley27, for the purpose ofcompressingair and feeding the compressed air tothe compression tank 29 to maintain sufficient airpressure to.

7 drive the material in the manner hereinafter described. The pressuretank is connected by means i of the pipe 51 with the upper portion ofthe charging chamber 46 and is therefore ready to supply compressedairto the charging chamber whenever the valve 52 is operated for thispurpose. I 1

Through the pulley 6- the belt 7 and the pulley 8 the shaft 9 is drivenand from there thepower is applied by the pulley 11, the belt 12, andthe pulley 13, to the shaftv 14 which carries the worm 1'7. i

This worm operates-the worm gear 18 and therefore drives thelongitudinally arranged shaft 19' at a speed which is much less; thanthe speed of the motor; due to the 1 reduction effected through the wormand worm gear drive. As the shaft 19 carries the cam disc- 37, thelatteris op erated in synchronism with the other parts of themachine andas the lever 3 3, 35 is operated from, this cam disc the-pump piston isreciprocated vertically in synchronismaWith the cam disc.

nt each revolution of the; cam disc, the pistonrod 34 makes astrokefirst downwardly and then upwardly. When the piston rod'movesdo'w'm'wmdlywiththe lever arm 33 the piston is-cross:

wise of .the'pump casing and as this piston'zmoves downwardlyit forcesthe. material. which is below'it from the pump casing through: the:pipe39 and into the charging chamber 46. lyprefer'to so design themachinethat the. capacitybf :the

charging chamber will be the same or approxb. I

mately the same capacity as thetpump in order that it may receive andhold temporarily :the same quantity of material which. is discharged inone operation of the pump; Although these proportions -may be variedmore or less, rend that when thisoharging chamber is about of thesame,capacityas the pump, the best. results are obtained because the chargingchamber iszfilled atonestroke'of the pump and is discharged'while thepump ismaking its return stroke.

During the downward movement of the piston,

iii-

as well as. at other times, the materialin the,

hopper 45 has a tendency to flow down by gravity 1 into the pump casingsothatv when the piston is movingdownwardly toforce the material which Yis below the piston out of the pump casing, the material from the hopperis flowing into the pump casing above the piston.

I When the lever arm 33 makes. its upward movement and raises the pistonrod 34 the piston iscaused to swing on its pivot 41 to the positionshown in Figure 6 by reason of thefweight' of material which above thepiston. This allows the piston to rise through the material which is"now about filling the pump casing and ;by the time the piston rodreaches its extreme upper posit-ion as shown in Figure 5, the pistonwill be swung by the spring 43 into the horizontal position shown inFigure 5. However, the piston'will operate in thismanner notwithstandingthe spring althoughsomewhat later because as soon as the,

piston rod startson its downward motion the greatest pressure of thematerial is below the piston and this forces it into the horizontalposition.

I-Icwever, Iprefer to use the light spring 43 in,

order to have the piston move to the horizontal- IlOSliZlOll while thepistonrod is in itsu'pper positron as shown in Figure 5.

motion of the lever 33, 35.

cylinder while the piston is making its downward stroke the pump casingis fillBd'il'llliil'lBlOl. downward stroke of the piston.

At each revolution of the cam discl37 thelever 66 is rocked upwardly anddownwardly by means of the pin or roller'62 and this lever arm by reasonofthe links 63, 64 causes both'o'f the valves 52, 47 to be opened andclosed at the same time] Furthermore, at each revolution of ;the

cam disc the cam 59 acts on the'bellcrank lever 58 torock it and thusact through the wire or link 55 to rock the lever 54 and thusopen andeach.

These operations are repeated at eachr'ocking' The material .is some'-'what sluggish but since it is feeding intothe pump close the valve 52whichcontr-ols the supply-of compressed air to the upper portionof thecharging chamber. 7

These several operations are soitirned thatfthevalves 49 and 47 areheldopen during the time the piston is making its downward strokea'n'dtherefore the material is drivenout of-the pump casing by the downwardstroke'of' the pumnand is caused to travel through the pipe 39and'tofill the charging chamber 46.. v

' While this operation. isitakingplacalthe' valve 45. is held open sothat the 'air'in the charging chamber is allowed toescape-into.theopenuair' while :the material is. being forced-upwardlyfihto.

the charging chamber, thereby providing space for the reception of thematerial and allowing the charging chamber .to'be filled." Thiscondition exists while the piston is making its complete downwardstroke. At this time the valve 52 which controls the passage ofcompressed air into the charging chamber is closed, so that there is nocompressed air in the chargingchamber while the charge isbeing pumpedinto it. While the piston is making its upward stroke, both of thevalves 49, 47 are closed. When these valves are closed, the cam 59 onthe cam disc acts on the bell crank 58 to rock the lever 54 and-thusopen the valve 52. v

As'stated above, the valves 49,-47 are closed while the piston is makingitsupward stroke. While the valve 52 is open, the compressedair rushesfrom the compression tank'through the pipe 51.and into the upper portionof the charging chamber; and this compressed air forces the chargeof,material which had previously been supplied to the charging chamber,out of. the latter and through the hose 66 toa point where the materialis being applied to a wall.

, As the valves 49, 4'7 are closed at this time, the

charge cannot pass back into the pump'casing and it is compelled totravel out through the ho' As the valve 49 is also closed while thecompressed air is in the chargingchamber, the compressed air or thematerial in the charging cham ber cannot pass out of this release valve.At about the time the piston completes its upward stroke or priorthereto, the bell crank 58 rocks back to the position shown in Figure 2,so that the valve 52 is closed and the machineis ready for a repetitionof the operations just described.

It will be apparent that the operation of the several valves issynchronized in relation to the operation of the pump and there isnothing to'de-, stroy or interfere with this synchronization.

It will be apparent that the action of themachine is intermittent orpulsating, but since the machine may operate rapidly, the pulsations aresufiiciently close together to produce a practically steady flow ofmaterial through the nozzle. It will be apparent that the mechanismdescribed above may be duplicated by providing two'pumps and twocharging chambers operating in alternation for the purposeof maintaininga substantially constant flow if it is found that the pulsations of thesinglepump and charging chamber do not furnish a sufiiciently constantsupply of material. However, I have found that a single pump andcharging chamber produce a suificiently constant flow for all practicalpurposes.

The pump employed in this machine is very simple in construction andoperation, which is a desirable featurein handling material such asplaster. It is not necessary that the piston fit snugly to the Wall ofthe pump shell because of the somewhat sluggish nature of the materialandin order for the piston to be swung downwardly into the positionshown in Figure 6 it cannot be made 3 to fit snugly to the pump shellwhen in the horizontal position shown in Figures and 7.

This type of pump, in addition to being very simple, also provides forthe filling of the pump casing above the piston while the latter ismaking its downward stroke in order that there will be suflicientmaterial below the piston at the time r the latter moves into thehorizontal position shown the pump casing at all times, and the pumpcasing is practicallyfilled with the material at the time thepiston ismaking its upward stroke, as shown inFigure 6. .l

The machine is very simple and effective in its operation and thevarious parts operate in the necessary sequence and in synchronizationwith each other. By employing compressed air to drive the material fromthe charging chamber, the liquid and solid constituents of the materialare not separated nor doany parts of themachine become pluggedor cloggedby the material. By

the employment of a pump and a charging cham-.

ber I am enabled to charge the latter once with each, stroke of the pumpand then to discharge completely the charging chamber while the pumpcharging chamber adapted to receive the material.

delivered by said pump,means for discharging air from said chargingchamber while it is being charged withthe material by said pump and forclosing said discharge during return strokes of the pump, and-means fordelivering compressed air into said charging chamber during the returnstrokes of the pump to force the material from said charging chamber.

2. A machine for delivering fluid material, including means for holdingthe materiaL'a reciprocating pump for receiving the material and forpropelling it, a charging chamber and means connecting said pump andcharging chamber at one end oi the latter, means for discharging airfrom said charging chamber at the opposite end to which the material isfed thereto by saidpump and for closing said discharge during returnstrokes of. the pump, and .means for delivering compressed air into saidcharging chamber to force the material therefrom.

3. A machine for deliveringfluidmaterial, in-

cluding means for holding the material, a reciprocating pump forreceiving the material and for propelling it, a charging chamber andmeans connecting said pump and charging chamber at one end of thelatter, means for discharging air from said charging chamber "at theopposite end to which the material is fed thereto bysaid pump and forclosing said discharge during return strokes of the pump, and means fordelivering compressed air into said charging chamber at the opposite endto which'the material is delivered thereto 'by said pump for forcing thematerial from said charging chamber.

4. A machine for delivering fluid material, including means for holdingthe material, a reciprocating pumpfor receiving the material and forpropelling it; a charging chamber and means connecting said pump andcharging chamber at one end of the latter, means for discharging air'from said charging chamberat the opposite end to which the material isfed thereto by said pump and for closing said discharge during returnstrokes of the pump, and means for deliveringcompressed air into saidcharging chamber at the opposite end to which the material is deliveredthereto by said pump for forcing the material" from said chargingchamber, the capacity of said charging chamber correspondingapproximately from and for propelling it, a charging chamber adapted toreceive the material delivered by said pump, means connecting said pumpwith one end of said charging chamber, a valve controlling the passagebetween said pump and said charging chamber, a valve for discharging airfrom. said charging chamber, means for delivering compressed air intosaid charging chamber to force the material therefrom, a valve forcontrolling the delivery of compressed air to said charging chamber, andmeans for operating said severai valves so that said first two valvesare opened While the pump is making its discharging stroke and areclosed while the pump is makingits return stroke and so thatthe'compressed air valve is opened while the pump is making its returnstroke and closed while the pump is making its discharge stroke.

6. A machine for delivering fluid-material, including means for holdingthe material, a reciprocating pump for receiving the material therefromand for propelling it, a charging chamber and means connecting said pumpand one end of said charging chamber to permit the flow of the materialinto the charging'chamber, a valve for controlling the passage of thematerial into said charging chamber, a valve adjacent the opposite endof said charging chamber for discharging air therefrom while thematerial is moving into said chamber, means for delivering compressedair to the end of said charging chamber to which said latter valve isconnected, a valve for controlling the feed. of the compressed air tosaid charging chamber and means for operating said valves in timedrelation whereby said first and second valves are opened during thedriving stroke of said pump and closed during the return stroke of saidpump and whereby said compressed air valve is opened while the pump ismaking its return stroke and closed while it is making its drivingstroke.

7. A machine for delivering fluid material, including means for holdinga supply of the material, a pump having a cylinder in continuouscommunication with said supply, a piston rod and a piston pivotallyconnected therewith, whereby said piston may lie crosswise of thecylinder during one stroke thereof, and move to a non-crosswise positionduring the opposite stroke of the piston rod, whereby the piston maymove upwardly through the material on its return stroke,

and a charging chamber into which said pump is adapted to deliver thematerial, and means for delivering compressed air into said chargingchamber to force the material therefrom.

, 8. A machine for delivering fluid material, including means forholding a supply of material; a pump having a cylinder for receiving thematerial from said supply, and a piston rod, for operating the pump, arocking lever for operating said piston rod, a cam disc and meansconnecting it with'said lever whereby the cam disc rocks said lever, acharging chamber into which the material is adapted to be delivered bysaid pump, a valve controlling the passage of material between said pumpand charging chamber, a valve for discharging air from said chargingchamber while the charge is being fed thereto, means for deliveringcompressed air to said charging chamber, and a valve for controlling thesame, and means all operated from said cam disc for operating saidseveral valves.

9. A machine for delivering fluid material, in-

cluding means for holding a supply of material,

a reciprocating pump for receiving the material therefrom, a chargingchamber and means connecting said pump and charging chamber, a valvecontrolling the passage of material between the pump and chargingchamber, a valve for discharging air from said charging chamber, meansfor feeding compressed air to said charging chamber, and a valve forcontrolling the same, a'lever for operating said pump, a'cam disc andmeans connected therewith whereby. the cam disc acts through a crankmotion to operate said lever, and a plurality of levers operated by saidcam disc, one of said last levers connected with said first two valvesand the other connected with the valve for feeding the compressed air tocharging chamber.

10. A machine for delivering fluid material, including means for holdinga supply of the material, a pump for receiving the material from saidsupply, a charging chamber and means for connecting said pump with oneend of said charging chamber and provided with a valveto control thepassage of material between the pump said

